As portable computing devices become more advanced, higher processing demands required to deliver advanced features produce increasingly greater amounts of heat. When the portable computing devices do not include active cooling devices, such as for example fans, heat can become trapped in isolated areas of the device in which the heat is generated. For example, when different subassemblies of the device are not in direct contact (e.g. separated by an air gap), heat transfer is limited to convection and radiation. While these two forms of heat transfer are generally acknowledged to be substantially less efficient than thermal conduction, the lack of a fan to circulate air through the device further reduces the efficiency of convective heat transfer. Consequently, devices with components that generate heat that are separated from other portions of the device will generally be unable to distribute heat throughout the device in an efficient manner. This deficiency can limit the amount of heat safely generated by such a device and in turn limit an amount of time the device can operate at peak operating speeds.
While it should be noted that highly thermally conductive sheets are available and in use for spreading heat across a surface of a subassembly, these thermally conductive sheets are most efficient at transferring heat in plane and thus are not well suited for use as a means for bridging a gap between separated subassemblies of a device.